Method for setting and dyeing boarded articles of synthetic fibers

ABSTRACT

BOARDED ARTICLES OF SYNTHETIC FIBERS FARE SET AND DYED IN A SEALED AUTOCLAVE INTO WHICH AIR UNDER PRESSURE HAS BEEN INTRODUCED BEFORE THE ADMISSION OF STEAM INTO THE AUTOCLAVE. A LIQUID DYESTUFF, OR A MIXTURE OF SUCH A DYESTUFF AND OTHER INGREDIENTS, IS ADMITTED TO THE AUTOCLAVE AT A TEMPERATURE OF LESS THAN 100 DEG. C., T HUS PRECLUDING THIS LIQUID TO TURN INTO STEAM. THE LIQUID IS CIRCULATED AND RECIRCULATED INSIDE OF THE AUTOCLAVE, AND SUPERHEATED STEAM UNDER PRESSURE IS INTRODUCED INTO THE SAME. THIS STEAM RAISES THE TEMPERATURE OF THE DYEING LIQUID WITHIN THE AUTOCLAVE AND IS COOLED AND CONDENSED BY SAID LIQUID. THE ADMISSION OF SUPERHEATED STEAM IS LIMITED IN QUANTITY AND TIME SO THAT THE TEMPERATURE OF THE DYEING LIQUID   THEREIN DOES NOT EXCEED THE VAPORIZATION TEMPERATURE THEREOF AT THE SUPERATMOSPHERIC PRESSURE PREVAILING INSIDE THE AUTOCLAVE.

Jan. 26, 1971 c. KRONSBEIN 3,557,395

METHOD FOR SETTING AND DYEING BOARDED ARTICLES OF SYNTHETIC FIBERS FiledMay 9, 1969 I I u 1 IIII E pi MINI! mmvroa:

Cu rt Kronsbein NMMMMMW.

United States Patent- Ofice U.S. Cl. 8149.2 4 Claims ABSTRACT OF THEDISCLOSURE Boarded articles of synthetic fibers are set and dyed in asealed autoclave into which air under pressure has been introducedbefore the admission of steam into the autoclave. A liquid dyestuff, ora mixture of such a dyestulf and other ingredients, is admitted to theautoclave at a temperature of less than 100 deg. 0., thus precludingthis liquid to turn into steam. The liquid is circulated andrecirculated inside of the autoclave, and superheated steam underpressure is introduced into the same. This steam raises the temperatureof the dyeing liquid within the autoclave and is cooled and condensed bysaid liquid.

The admission of superheated steam is limited in quantity and time sothat the temperature of the dyeing liquid therein does not exceed thevaporization temperature thereof at the superatmospheric pressureprevailing inside the autoclave.

BACKGROUND on THE INVENTION The numerousprior art methods for settingand dyeing boarded articles of synthetic fibers are subject to seriouslimitations. One such process involves treatment of the boarded articleswith steam Within the range of 10.0 deg. C. and about 166 deg C. (or 2l2deg. F. to 330 deg. F.) and a liquid dye, and maintaining theaforementioned steam condition constant, i.e. subjecting the articles toa substantially uniform temperature during the process of setting anddyeing. I

The pressure of steam and of a liquid dye in an enclosed autoclave atsubstantially the same temperature, both 3,557,395 Patented Jan. 26,1971 sion of compressed air is continued until the vaporizationtemperature of the liquid in the enclosure exceeds 100 deg. C.Thereafter the aforementioned liquid fiber-dyeing substance iscirculated and recirculated and the boarded articles are subjected inthe form of sprays to the action of said liquid substance. Finallysuperheated steam under pressure is admitted into said enclosure andcaused to condense therein. The admission of superheated steam isinterrupted when a predetermined temperature is reached inside theenclosure.

BRIEF DESCRIPTION OF THE DRAWING The drawing illustratesdiagrammatically in vertical section an autoclave system for carryingthe method according to this invention into effect.

DESCRIPTION OF PREFERRED MODE OF CARRYING THE INVENTION INTO EFFECT Themethod according to this invention lends itself well to heat setting anddyeing of hosiery of nylon 6, or nylon 66. To this end the article 2 tobe treated is boarded, i.e. mounted on support 3 substantiallyconforming to the shape of the particular article to be treated, i.e. inthe instant case conforming substantially to the shape of hosiery.Thereafter the boarded articles are introduced into an enclosure capableof withstanding internal pressures in excess of atmospheric pressure.Reference character 1 has been applied to designate a tank or autoclaveof this description. Tank or autoclave 1 is provided with a measuringcontainer 4 for liquid connected to tank or autoclave 1 by means ofvalve 6. Container 4 is intended to receive a liquid substance 5 capableof dyeing the constituent fibers of the boarded hosiery 2. The liquid 5may being subject to the same saturation pressure, makes it diflicult toachieve the required circulation and recirculation by means of amechanical pump. In the presence of foam-forming ingredients,circulation and recirculation become impossible. These conditions imposeserious limitations in regard to the quality of the dyeing action whendyeing is performed by the aforementioned method. The above methodinvolves an unstable vaporous medium which is conductive to unevensetting of the articles being treated by the method.

The process according to this invention eliminates these limit-actionsof the aforementioned method of heat setting and dyeing articles made ofsynthetic fibers.

Another aspect of the process according to this invention is to reducethe time involved in setting and dyeing the boarded articles ofsynthetic fibers without adversely affecting the setting and dyeingprocess by the presence of an atmosphere of steam.

SUMMARY OF INVENTION be a dye plus other liquid hose treating media oringredients such as scouring media, acidulating media to control the pHvalue, and dispersion media to control the desired shade of the dye.There are many known formulae for such treating liquids and, therefore,such formulae do not need to be stated in this context. The temperatureof liquid 5 at the time of its admission through valve 6 into tank 1 isless than deg. C., and preferably about 80 deg. C. Upon admission ofliquid 5 into the autoclave or tank 1 the latter is tightly closed, orsealed, so as to preclude any escape of gaseous media from the inside tothe outside thereof. Thereupon the operation of pump 7 is initiated.This initiates circulation and recirculation of the liquid dyeingsubstance in tank 1. To be more specific, the dyeing substance issprayed by a system of sprayers 10 upon the boarded hose 2, then dropsinto sump 11 defined by tank 1, and is raised by pump 7 through conduitor pipe 12 to the level of sprayers 10. Simultaneously a valve 8 isopened admitting air under pressure from a source of air under pressure(not shown) into tank or autoclave 1. The admission of air underpressure into tank or autoclave 1 is continued until a predeterminedpressure level is established therein. This pressure level is preferablyin the order of 7 lbs./in. When the aforementioned predetermined orpreferred pressure level inside of enclosure 1 has been reached,superheated steam under pressure is admitted through valve 9 intoenclosure 1, and said steam is caused to condense Within enclosure 1.The superheated steam admitted through valve 9 forms a heating mediumfor the liquid within, and is circulated and recirculated throughenclosure 1. The steam admitted through valve 9 condenses to water as itheats the dyeing fluid inside of tank or enclosure 1. The step ofadmitting steam to enclosure 1 is continued until the required dyeingtemperature within tank 1 has been reached. This temperature may be inthe order of deg. C. It has been found possible to raise the temperatureof the dye in tank 1 to 115 deg. C. within a period of 60 seconds by theadmission of superheated steam into tank 1. The dyeing and heat settingprocess is completed when the above referredto predetermined temperaturehas been reached, i.e. there is no need to maintain this temperature fora protracted period of time.

The temperature versus time characteristics which may be obtained by theadmission of superheated steam into tank 1 is virtually a straight line,or can be made to be virtually a straight line. It has been found that astraight temperature versus time characteristic in the range from about70 deg. C. to about 115 deg. C. is an essential prerequisite forachieving an optimum of uniformity in carrying out the dyeing and heatsetting method according to this invention.

There is no fixed pressure that must be established i'lside of enclosure1 by the admission of air under pressure through vale 8 (nor is thereany fixed temperature at which the dye must be admitted through valve 6into enc osure 1, except that this temperature ought to be less than 100deg. C. It is, however, essential that the pressure and temperatureprevailing within enclosure 1 prior to admission of superheated steaminto it and the admission of superheated steam into said enclosure areso correlated that the superheated steam condenses upon admissionthereof into enclosure 1. In other words, the temperaturev withinenclosure 1 should not be raised by the admission of steam to the pointwhere condensation of that steam does not occur any longer.

While I have described by way of illustration a particular processaccording to the present invention, it will be apparent that theinvention is not limited to the specific data used to illustrate thesame.

What I claim as new and desire to secure by Letters Patent of the UnitedSattes is:

1. A method for setting and dyeing boarded articles of synthetic fibersincluding the steps of (a) mounting textile articles on boardsconforming substantially to the shape of said articles;

(b) introducing said boarded articles into an enclosure capable ofwithstanding internal pressures in excess of atmospheric pressure;

(c) admitting into said enclosure a liquid substance capable of dyeingthe constituent fibers of said articles, said liquid substance having atemperature of less than 100 deg. C. when admitted into said enclosure;

(d) admitting compressed air into said enclosure and thereby increasingthe vaporizationtemperature of said liquid in said enclosure andcontinuing the admission of compresed air into said enclosure until thevaporization temperature of said liquid in said enclosure exceeds deg.C.;

(e) circulating and recirculating said liquid substance and subjectingsaid boarded articles to the action of said liquid substance in the formof sprays thereof; and

(f) admitting superheated steam under pressure into said enclosure andcausing condensation thereof within said enclosure.

2. A process as specified in claim 1 wherein said liquid substance isbeing admitted at a temperature of about 80 deg. C. and not less than 70deg. C. into said enclosure.

3. a process as specified in claim 1 wherein said compressed air isadmitted to said enclosure until the pressure prevailing therein attainsthe order of 7 lbs./in. above atmospheric pressure.

4. A process as specified in claim 1 including the steps of socorrelating the pressure and the temperature prevailing within saidenclosure prior to admission of said superheated steam into saidenclosure and the admission of steam into said enclosure that saidsuperheated steam condenses upon admission therof into said enclosure,and interrupting the admission of superheated steam into said enclosureat a point of time before the temperature of the .liquid containedtherein reaches the vaporization temperature thereof.

References Cited UNITED STATES PATENTS 2,874,884 2/1959 Heliot 223-762,915,230 12/1959 Brewin et al. 223-76 2,985,502 5/1961 Kronsbein et al.815O 3,468,539 9/1969 Swindall 223-76 JORDAN FRANKLIN, Primary ExaminerG. V. LARKIN, Assistant Examiner US. Cl. X.R.

